In a classic 1991 episode of The Simpsons, Lisa is distraught to learn that her inspirational substitute teacher, Mr. Bergstrom, is leaving her.

With his train ready to leave the station, Mr. Bergstrom writes Lisa a note. "Whenever you feel like you’re alone, and there’s nobody you can rely on, this is all you need to know," he says. Lisa opens the note as Mr. Bergstrom’s train disappears into the distance. It reads, "You are Lisa Simpson."

Yeardley Smith, who’s been voicing 8-year-old Lisa since 1987, was in her twenties when the episode was made. She was flown to New York to record her lines opposite Dustin Hoffman, who voiced Mr. Bergstrom. It was a career highlight.

But she didn’t quite comprehend that note.

"I remember reading that and going, that’s it? That’s all you have for my girl? I so didn’t get it. Fucking hell. That’s all she has to go on?! I was like, I don’t know what the fuck you’re talking about. I don’t know what this means."

Smith sounds almost exactly like Lisa—which can make it feel weird, and more than a bit wrong, to hear her cuss. "Oh, my holy fuck," she says at the mention of an episode from 2000 that envisages Lisa Simpson succeeding Donald Trump as president. "Yes! Oh! If only. Oh my god. Ugh."

But for 29 seasons—the 30th premieres this fall—the only major character Smith has voiced has been Lisa. “I’m not that clever,” says Smith, with a girlish giggle that makes her sound even more like her character.

Smith has even been banned from playing background characters in Springfield. “The word came down: ‘Yeardley, you’re not allowed to be in the crowd unless Lisa Simpson is in the crowd. The timbre of your voice is too specific, and you always bleed through, and we can’t have it.’”

The point has been driven home at the Simpsons cast’s occasional live appearances over the years. Each of Smith’s colleagues get introduced along with the impressive list of characters they play. “And then you would get to me. ‘Yeardley Smith . . .’” (Long pause.) “‘Lisa Simpson . . .’ And I would think, ah, fuuu . . . I just . . . ugh . . .” Smith laughs. “All the flowers in the bed were blooming, standing up straight, proudly, and my flower just kind of drooped a little bit.”

I ask Smith if it feels, perhaps, like getting stuck eating crackers while everyone around her feasts at a bountiful and ever-expanding banquet.

“I feel like it’s more like being in a circus. Like being part of a circus performing family. But you’re not talented enough to do all the flips, so all you get to do is stand on the end of the seesaw that everybody else jumps off of.” Smith laughs. “You’ve got to have a tough skin in this business.”

If your identity has to be inextricably intertwined with that of a single cartoon character, you could do worse than Lisa Simpson.

Simpsons creator Matt Groening has described Lisa as the only character on the show not controlled by his or her base impulses. More than that, Lisa is the family’s, and the series’s, moral center and voice of reason. She’s a precocious reader, a preternaturally talented musician, an ardent feminist, a vegetarian, an environmentalist, a Buddhist, a champion of scientific reason, a grassroots activist, an eloquent orator, a fiercely independent thinker, and an all-round bastion of social justice. “Democrats are the party of Lisa Simpson,” as Senator Ted Cruz put it, during February’s Conservative Political Action Conference. “And Republicans are happily the part of Homer, Bart, Maggie, and Marge.” (The first part, at least, is true.)

In any given episode, she might read Walt Whitman’s Leaves of Grass out loud to soothe a beached whale, genetically engineer a tomato to cure world hunger for a science-fair project, or design a talking doll that possesses the “wisdom of Gertrude Stein” and “down-to-earth good looks of Eleanor Roosevelt.”

As if in an outward display of her inner complexities, she also happens to be the most complicated Simpson family member to animate, her sunburst-do defying the natural principles of geometry. (The jagged hem of Lisa’s Flintstonian dress, which gives her the silhouette of a shuttlecock, is trickier to explain.) And as the episode “Bart Gets Famous” suggests, she may also be the only Springfield resident without a catchphrase. (“If anyone wants me,” she deadpans instead, “I’ll be in my room.”)

In the original, scraggily drawn Simpsons shorts that ran on The Tracey Ullman Show from 1987-89, Lisa was Bart’s hell-raising accomplice. It was producer James L. Brooks—former producer of The Mary Tyler Moore Show—who pushed for Lisa to be a child prodigy of some kind.

Lisa became a sax player. It was partly a visual gag—Groening was amused by the sight of a little girl wielding the bulky, odd-shaped instrument—but the sorrowful tones of the baritone saxophone also strongly implied that Lisa possessed an intelligence and reservoirs of feeling well beyond her years. In 1996, The New York Times reported that Lisa was inspiring a “sax craze” among young girls. Two years earlier, Lisa had appeared in a feature in Ms. magazine on “The Many Faces of Feminism.”

The first Lisa-centric episode, “Moaning Lisa,” was written by Mike Reiss and Al Jean, who’d cut their teeth as gag writers for National Lampoon magazine and The Tonight Show. “We jumped at the chance to write for Lisa,” says Jean, now the Simpsons longtime show-runner. “We really wanted to write something with heart. You get humor, but also such vulnerability and emotion from Lisa Simpson.”

“I think my favorite thing about Lisa Simpson is her resilience. Oh,
that I could be that resilient!”

“She cares and feels so deeply about things,” says David X. Cohen, writer of key Lisa episodes “Lisa the Vegetarian” and “Lisa the Skeptic.” “It’s great for developing dramatic story lines. If you believe Lisa truly cares about something, then you will, too.”

“Lisa’s basically a huge nerd, yet you don’t feel like punching her in the face every time she says something smart,” says Cohen. “Contrast this to Martin Prince, whose personality is that he can’t help rubbing it in your face how smart he is. With Lisa, you just feel like hugging her. She just wants what’s right, a world ruled by logic and justice. It’s a tricky performance Yeardley pulls off. She makes Lisa into the type of nerd that every nerd aspires to be. The kind that doesn’t get punched in the face.”

Another successful Simpson family Daddy-Daughter Day.

From 20th Century Fox Film Corp./Everett Collection.

The relationship between Homer and Lisa—the pairing of diametrical opposites in Lisa’s sensitivity and sincerity and Homer’s buffoonery—is also arguably the richest and most affecting relationship in the show. It can be emotional for the performers, too: Smith admits to breaking down while recording the scene in “Lisa’s Substitute” in which Lisa lashes out and calls Homer a baboon.

“Speaking very personally, I had a sometimes-wanting relationship with my own father,” she says. “So, to be able to play these scenes with Homer, where she actually feels like he gets her, really ticks a very personal box for me. I always feel that they write that stuff really beautifully. There have been so many episodes where they have a meeting of minds, when Homer goes out of his way to at least try to understand Lisa—and often admits, ‘I still don’t understand you, but I love you deeply. I’m really happy to be here with you and that’s enough for me.’ What’s better than that, really?”

None of this takes away from the comic potential of the character; if anything, there’s an extra delight when Simpsons writers coax Lisa into more outrageous situations. When she regally proclaims, “I am the Lizard Queen!”—trembling, blanched of color, and buzzed on Duff Beer—it’s funnier because it’s her.

“If you believe Lisa truly cares about something, then you will, too.”

But more often, Lisa is Springfield’s and The Simpsons’ resident idealist and bleeding heart. It’s a role that sets her up for regular disillusionment and crushed spirits.

Apart from her teary farewell with Mr. Bergstrom, Lisa has had to part ways with a beloved pony (“Lisa’s Pony”), grieve for her musical mentor (“’Round Springfield”), endure her vegan crush being thrown in jail (“Lisa the Tree-Hugger”), and watch her first saxophone get unceremoniously crushed (“Lisa’s Sax”). A 23-year-old Lisa calls off her wedding in the time-shifting “Lisa’s Wedding,” and, in “HOMЯ,” she bonds with a new, sympathetic and intelligent version of Homer, only for him to revert to his baser self by the end of the episode. When she finally, and effortfully, makes real friends in “Summer of 4 ft. 2,” it’s on summer vacation, far away from Springfield, and the friends are never to be seen on the show again.

Just as Wile E. Coyote is destined to never catch the Road Runner, there’s a comparable existential futility to Lisa’s lot on The Simpsons—an eternity of being profoundly unappreciated, unable to make a difference and, as she sings in “Moaning Lisa,” “the saddest kid in grade number two.”

“For me, the tragic side of Lisa is that they put her through so much loss, over and over,” says Smith. “She never has any friends; when she’s good at something she’ll meet somebody who’s better at it. Her victories are hard fought and briefly enjoyed.”

If Lisa Simpson has endured a disproportionate amount of suffering and strife over the years, Yeardley Smith has spent much of her life grappling with troubles of her own.

Smith was 5 years old when she felt a love of performing for the first time. Her childhood aspirations were huge—a best-actress Oscar by 20 was part of the plan—but laced with insecurities and anxieties, a “bottomless pit” of self-doubt.

“I thought from this very, very young age—as many people who don’t have experience with fame, large or small, do—if I can just get the world to adore me, then I will feel better about myself and all my insecurities will go away. Everybody will adore me, and that must mean that I’m worthwhile.”

Smith began dieting when she was 9. Soon, she was obsessed with her weight, thinking of her body as “the enemy,” convinced that her inability to get thin was a personal failing. When she was 14, a friend persuaded her of the benefits of vomiting after eating. Smith binged and purged like her future happiness depended on it. The accompanying release of endorphins was not dissimilar to the high she felt when performing.

In 1984, Smith made her Broadway debut in Tom Stoppard’s The Real Thing. It was her big break, but didn’t make her feel any more creatively fulfilled. Similarly, even as The Simpsons became a massive hit, voicing Lisa “didn’t count” in Smith’s equation for success. Being a voice actor—employing a voice for which she’d been teased all her adult life—was merely acting “from the neck up”.

Damaging as that conviction was, the notion seemed to be reinforced by the industry. In 1992, Smith received a Primetime Emmy Award for outstanding voice-over performance—a Creative Arts Emmy, presented at an un-televised event separate to the ceremony proper. At the actual Emmys a week later, Smith was a presenter, but her own Emmy win went unacknowledged. When she got home she stashed the award in the back of a closet.

“I think the disappointment was not so much that I didn’t enjoy voicing this truly wonderful character, but that it wasn’t filling up this hole inside of me,” she says. “I remember feeling I must not be doing this right, because I don’t feel more full inside. So, it must be my fault. And that’s a really . . . that’s a devastating place to find yourself in.”

“She makes Lisa into the type of nerd that every nerd aspires to be.
The kind that doesn’t get punched in the face.”

In the 90s, Smith had recurring roles on Herman’s Head and Dharma & Greg, and made the occasional one-off appearance on other shows. Already exercising compulsively, she spent more than $40,000 on plastic surgery, including cheek reduction and eyelid-tucking treatments, believing that she needed to physically transform to get more work.

But despite landing a decent part in 1997’s As Good as It Gets, the roles and opportunities continued to shrink. Where she’d once played the “best-friend” role, she found herself downgraded to playing “the friend of the friend.” As her career faltered, her feelings of self-loathing and failure intensified. Her bulimia—about which she told no one—was out of control. There were times when she threw up blood.

According to Smith, one of the biggest obstacles between her and acting work was her voice.

“I was getting older, but I still sounded and looked very young,” she says. “I didn’t seem old enough to play anybody’s mom. [But] I couldn’t play anybody’s daughter anymore, which had been my calling card for so long.”

“And it was very confusing to me, and I sort of had this identity crisis. I felt like, I am what I do, and now I don’t get to do it as much as I used to. So who am I?”

It took 25 years for Smith to overcome her eating disorder and conquer her nagging feelings of inadequacy. The milestone of turning 40, which she dreaded, turned out to be an unexpected relief, as if absolving her of the pressure to achieve all her life goals by that arbitrary deadline.

Smith wrote a one-woman show—a cardboard cutout of her cartoon alter-ego featured prominently—performing it in New York and Los Angeles. The show was an autobiographical-cautionary tale, expressing the lesson she was only beginning to grasp: “Do not attach your identity to your work. Attach your identity to things that are to your own personal growth that mean something to you on the inside. Because you can’t fill up the inside from the outside.”

And amazingly, after all these years, Mr. Bergstrom’s handwritten note to Lisa—“You are Lisa Simpson”—finally sunk in. “I went, Oh my god. All you need is already inside of you. To actually admit that is such an admission of the fact that I obviously didn’t feel, and still struggle with the notion that everything I need is inside of me.”

Smith went on to achieve a level of career satisfaction largely by making work for herself. Since her one-woman show, she has written a children’s book, launched a women’s luxury shoe line, and gotten into film production. She is currently lending her voice to the true-crime podcast Small Town Dicks, which she also produces. (If it’s startling to hear the voice of Lisa Simpson use salty language, wait till you hear it recount the details of a grisly murder: “We have an interview with a sexual predator you won’t believe,” she enthuses.)

As difficult a time as Lisa Simpson has on The Simpsons, Smith points out that there’s also something inspiring about the character’s dogged determination in the face of that hardship.

“I think my favorite thing about Lisa Simpson is her resilience. Oh, that I could be that resilient! And I will say, if I’ve learned anything from her, I’ve learned that.”

For the record, Smith disowns her long-ago remark about acting “from the neck up,” and affectionately refers to Lisa as “my girl” multiple times during our interview. For Smith, Lisa Simpson has clearly been the role of a lifetime.

“She’s so beautifully fleshed out. In the animation, and the writing and, hopefully, in the performance, that I feel as though she exists quite separately from me,” says Smith. “I really feel like—I honestly feel this—it’s been such an honor to embody a character that I would look up to. And then, the icing on the cake is that other people look up to her too. She’s so who I wish I could be.”

The Big Orange Couch, Nickelodeon

For a generation of viewers, nothing said “stay up past your bedtime” like the inviting orange sofa that served as SNICK’s official mascot.

Photo: Courtesy of Nickelodeon.

The Couch at Central Perk, Friends

Really, those orange cushions were the seventh friend. (Sorry, Gunther.)

Photo: From Everett Collection.

The Simpson Family’s Couch, The Simpsons

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Photo: From 20th Century Fox/Everett Collection.

D’Angelo Barksdale’s Orange Sofa, The Wire

Another orange couch—but this one is outside! And also a perfect meeting spot for Baltimore’s drug dealers.

Photo: From HBO/Photofest.

Don’s Office Couch, Mad Men

From pitches to hangover naps to ill-advised hookups, this was one of the hardest-working couches in show business.

Photo: By Carin Baer/AMC/Everett Collection.

Blanche, Rose, Dorothy, and Sophia’s Couch, The Golden Girls

Does it get more Florida fabulous than this squashy bamboo dream?

Photo: From Touchstone Television/Everett Collection.

Olivia’s White Couch, Scandal

Red wine, white couch? Only Olivia Pope could combine them without fear.

Photo: By John Fleenor/ABC.

The Big Orange Couch, Nickelodeon

For a generation of viewers, nothing said “stay up past your bedtime” like the inviting orange sofa that served as SNICK’s official mascot.

Courtesy of Nickelodeon.

The Couch at Central Perk, Friends

Really, those orange cushions were the seventh friend. (Sorry, Gunther.)

From Everett Collection.

The Simpson Family’s Couch, The Simpsons

The opening credits have transformed it into a giant whack-a-mole game, an electric chair, and a roller coaster, among countless other objects—but at heart, the Simpson family’s couch will always be the center of their all-American home.

From 20th Century Fox/Everett Collection.

D’Angelo Barksdale’s Orange Sofa, The Wire

Another orange couch—but this one is outside! And also a perfect meeting spot for Baltimore’s drug dealers.